I have these hawthorns naturalized wild in my back woods. They are not my native Crataegus douglasii, and I had it pegged for C. monogyna until I looked at the photos under that listing, which don't quite match up. It is a smallish tree, with stinky (to me) white flowers, sharp thorns, and small berries (I forget what color and there are none on any now). Perhaps there is just some divergence from the ones in the database which I believe are mostly south of me. Or...??

How about C. phaenopyrum?

http://www.pnwplants.wsu.edu/P...

Washington Hawthorn (Crataegus phaenopyrum)

Could be Crataegus laevigata, you have it in WA but I don't think it quite matches up.

http://apps.rhs.org.uk/plantse...

http://luirig.altervista.org/s...

Crataegus monogyna does look to be correct .. there's several photos which show leaf variation..

http://luirig.altervista.org/s...

After reviewing all the web sites you so kindly provided, I agree that the best match appears to be C. monogyna and my leaf pattern is just a bit more lobed than the ones in the ATP database. C. phaenopyrum is a multi-stemmed tree, which mine is not. I don't recall what the fall foliage is like, although I don't recall it being 'fantastic' which was another descriptor for C. phaenopyrum. I wish I would have gotten a photo of the blossoms this year, that would have been another clue. I'll plant to take more photos at different times of the year. I will hold off posting any photos in the ATP database until I have a firm ID, but for my own personal database it'll stay under C. monogyna. Thanks for your assistance.